In this study, we present an effective tight-binding model for an accurate description of the lowest energy quadruplet of conduction band in a ferromagnetic CrX3 monolayer, tuned to the complementary \textit{ab initio} density functional theory simulations. This model, based on a minimum number of chromium orbitals, captures a distinctively flat dispersion in those bands but requires taking into account hoppings beyond nearest neighbours, revealing ligand-mediated electron pathways connecting remote chromium sites. Doping of states in the lowest conduction band of CrX3 requires charge transfer, which, according to recent studies, can occur in graphene(G)/CrX3 heterostructures. Here, we use the detailed description of the lowest conduction band in CrI3 to show that G/CrI3/G and G/CrI3 are type-II heterostructures where light holes in graphene would coexist with heavy electrons in the magnetic layer, where the latter can be characterised by Wigner parameter rs∼15−20 (as estimated for hBN-encapsulated structures).
@article{arxiv.2404.18858,
title = {Correlated Electron Effects in Chromium Trihalide Hetostructures with Graphene: A Tight-Binding Model Perspective},
author = {Igor Rozhansky and Vladimir Fal'ko},
journal= {arXiv preprint arXiv:2404.18858},
year = {2024}
}